/*
 * errormsg.c - functions used in all phases of the compiler to give
 *              error messages about the Tiger program.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include "util.h"
#include "errormsg.h"

bool anyErrors= FALSE;

static string fileName = "";

static int lineNum = 1;

int EM_tokPos=0;

extern FILE *yyin;

typedef struct intList {int i; struct intList *rest;} *IntList;

static IntList intList(int i, IntList rest) 
{
	IntList l= checked_malloc(sizeof *l);
	l->i=i; l->rest=rest;
	return l;
}

static IntList linePos=NULL;

void EM_newline(void)
{
	lineNum++;
	linePos = intList(EM_tokPos, linePos);
}

void EM_error(int pos, char *message,...)
{
	va_list ap;
	IntList lines = linePos; 
	int num=lineNum;

	anyErrors=TRUE;
	while (lines && lines->i >= pos) {
       lines=lines->rest; num--;
	}

	if (fileName) fprintf(stderr,"%s:",fileName);
	if (lines) fprintf(stderr,"%d.%d:  --------- error --------  ", num, pos-lines->i);
	va_start(ap,message);
	vfprintf(stderr, message, ap);
	va_end(ap);
	fprintf(stderr,"\n");
}

void EM_reset(string fname)
{
	anyErrors=FALSE; fileName=fname; lineNum=1;
	linePos=intList(0,NULL);
	yyin = fopen(fname,"r");
	if (!yyin) {EM_error(0,"cannot open"); exit(1);}
}

/* 格式化打印内容与当前位置 */
void EM_pfun(int pos, char *message,...)
{
    va_list ap;
    IntList lines = linePos;
    int num=lineNum;

    anyErrors=TRUE;
    while (lines && lines->i >= pos) {
        lines=lines->rest; num--;
    }

    if (fileName) fprintf(stderr,"%s:",fileName);
    if (lines) fprintf(stderr,"%d.%d: ", num, pos-lines->i);
    va_start(ap,message);
    vfprintf(stderr, message, ap);
    va_end(ap);
    fprintf(stderr,"\n");
}
